This application claims the priority of German Application No. 198 44 784.1, filed Sep. 30, 1998, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a method for determining and optionally eliminating a disturbing noise subjectively perceived by an operator, particularly a disturbing vehicle noise, which is subjectively perceived by an operator of the vehicle, and particularly of a motor vehicle, used, for example, in the automobile industry and assumed to be known here.
From German Patent Document DE 195 31 402 A1, a method is known in which, for influencing the subjectively perceived driving impression as a function of a parameter (particularly as a function of the rotational engine speed and/or of the vehicle velocity), not only the airborne sound is influenced but also the structure-borne sound or vibrations perceived by the body. For this purpose, according to the size of the parameter, certain data are read out of a data field and, by means of vibration generators, are converted among others also into secondary vibrations which can be perceived by the body. Furthermore, the present sound effects are determined. The determined sound effects are compared with a comparative value filed (stored) in a data memory. If the determined comparative sound effects are above the comparative value at least at certain frequencies, the sound effects are converted by a mathematical algorithm, preferably a Fourier transform, into a frequency spectrum. The frequency spectrum is compared with frequency spectrums which have known error causes and are stored in a data and/or noise memory, and information is emitted concerning a required repair. If the frequency sequence, which is the result of the disturbing noise, and its cause are known, a corresponding repair can simultaneously be indicated and be carried out in a repair shop.
If, in the case of a vehicle, there is a complaint concerning a disturbing noise in the sound effects, it is difficult in some cases to find the pertaining cause. In particular, these difficulties are caused by the fact that the human language knows no mathematically clear terms for certain noises. Furthermore, the absolute acoustic memory, even in the case of acoustically trained individuals, is limited to no more than a few minutes.
In addition to disturbing noises in the above-mentioned vehicles, disturbing noises, whose cause should be eliminated, also occur on other equipment, such as processing machines, household appliances, etc.
It is an object of the invention to provide a method which improves upon the finding and eliminating of causes from which subjectively perceived disturbing noises result.
This object is achieved according to the present invention by a method for determining, and optionally eliminating, a subjectively perceived disturbing noise, particularly a disturbing noise which is perceived by an operator of a vehicle, in particular a motor vehicle. The invention is characterized by the jointly carried out process steps wherein: (a) the disturbing noise is recorded in the presence of the operator who has made the complaint; (b) the sound effects are recorded particularly in the region of the operator""s ear; (c) a noise sequence, which contains the disturbing noise, is taken from the overall sound effects; (d) the noise sequence is played to the operator; (e) if the noise sequence is at least similar to the disturbing noise, the noise sequence is converted to a sequential frequency spectrum by means of a mathematical algorithm; (f) in the present sequential frequency spectrum, at least one frequency or group of frequencies, in the following simplified as xe2x80x9cfrequency sequencexe2x80x9d, is manipulated; (g) from the manipulated frequency spectrum, a manipulation noise is generated and is played to the operator for evaluating the change of the disturbing noise; and (h) if the disturbing noise is reduced or remote in the manipulation noise, a corresponding measure, particularly a repair, is carried out.
By means of the method or device according to the invention, it is possible to make the subjectively perceived disturbing noise at least partially objective and to optionally store it, in particular, on an electronic data carrier. By means of corresponding apparatuses, this impression can then be felt again or heard in a reproducible manner at any time. For localizing the cause of a disturbing noise, at least a single frequency is manipulated. The manipulation takes place particularly by means of at least one low pass, high pass and band pass filter, or an element or algorithm acting in this manner.
In addition, as the result of the claimed measures, the so-called acoustic memory, that is, the precise memory of the impression during the actual operation of the vehicle, is replaced by a reproducible recording and can therefore be prolonged by any extent.
Furthermore, as the result of the claimed method, repair costs are also reduced, which, in particular, is the result of saving time when finding the causes of the disturbing noises. In addition, the servicing is improvedxe2x80x94among other things, by the saving of timexe2x80x94and customer satisfaction is increased.
In the automotive field, in a further development of the invention, the disturbing noises can also be classified according to the vehicle model, the motorization, the equipment, the operating conditions at which the disturbing noises occur, etc., and may be retrievable.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.